UMTS WCDMA Radio Network Planning using Beamforming Techniques

The issue of UMTS WCDMA radio network planning with beamforming antenna arrays (AAs) at the base station, synthesizing a grid of beams, is discussed in this paper. With the help of a static network simulator, two possible beamforming solutions in UMTS are presented and compared. In the first method each beam has its own primary common pilot channel (P-CPICH) and represents a logical cell transmitting under a unique primary scrambling code. In the second method each beam is associated with a unique secondary common pilot channel (S-CPICH) and different beams are scrambled with the same scrambling code in order to preserve orthogonality. Simulation results show that the first method is less attractive due to higher soft handover overhead and lower system capacity.